PolitiFact: Sorting out the truth on marijuana

Thanks to a Florida Supreme Court decision on Monday, Florida voters will weigh in this November on a constitutional amendment to allow the medical use of marijuana. Around the country, 20 states plus the District of Columbia have already taken that step, and Colorado became America's testing ground when recreational marijuana use became legal this year.

All you need do is look at national polls to see that the country is at a tipping point. The public is split on legalizing marijuana altogether and large majorities favor making marijuana legal for medical use.

The marijuana discussion has kept PolitiFact and PunditFact busy. Since the start of 2013, we've tackled claims related to pot 15 times, with 10 coming in the past six months.

Here are six claims that capture the ongoing debate.

People on pot "shoot each other . . . stab each other . . . strangle each other, drive under the influence, kill families," Nancy Grace, Jan. 14

The HLN host spoke to the darkest fears about marijuana users. Grace, a one-time prosecutor, said she had seen people high on pot "wipe out a whole family."

We found a few individual cases that support her point, but there's no evidence that marijuana itself drives people to commit violent acts. Dr. Ihsan Salloum, professor of psychiatry at the University of Miami Miller School of Medicine told us the clear majority of users don't become aggressive.

We rated the claim Mostly False.

"Nobody's addicted to" marijuana, John Morgan, Sept. 22, 2013

Promoters of legalization can go too far sometimes. Orlando lawyer John Morgan made this claim during a television debate but soon apologized for making a "huge mistake." Dependence is hardly common, but it does happen in about 9 percent of all users, according to the National Institute of Drug Abuse. We rated Morgan's claim False.

The popular Fox News host lent his weight to the concern that any veneer of acceptability will lead to runaway use of marijuana. The Denver Post's plans to track the unfolding of legalized recreational use in Colorado drew O'Reilly's ire. The newspaper said this was a very big story that merited coverage from all sides, including supporters, opponents and all views in between.

O'Reilly later told us he didn't mean to say that the Post was promoting pot. Yet we counted him making that point nine times during his show. We rated O'Reilly's claim False.

Colorado's grand experiment prompted a novel allegation from one of the co-hosts of Fox and Friends. While it's true that food stamp recipients get an electronic benefits card from the state, ATMs won't treat that as cash. It's against the law and the government pays programmers to prevent it. Kilmeade would have had a point if he had talked about welfare benefits in general. But he didn't. We rated the claim False.

Marijuana today is "genetically modified," with THC levels that "far surpass the marijuana" of the 1970s, Patrick Kennedy, Jan. 21

President Barack Obama ignited a debate when he told a magazine interviewer that marijuana is no more dangerous than alcohol. Former congressman Patrick Kennedy opposes legalization and said the president needs to know that the typical weed today packs a bigger punch than it did when Obama was a teenager.

We found that the concentration of the main active ingredient in marijuana more than doubled from 1993 to 2008. The "genetically modified" part didn't hold up; marijuana is stronger due to selective breeding, not laboratory gene splicing. We rated Kennedy's claim Mostly True.

A video billboard at the Indianapolis Motor Speedway made this claim and sorting it out hinged on how you define toxic. Saying that pot is less toxic than alcohol doesn't mean that it is harmless. But in one key respect, marijuana is safer than alcohol.

A massive dose of alcohol can kill while the same has never been observed with marijuana. By one measure, alcohol is 100 times more toxic than marijuana. We rated this claim Mostly True.

Read more fact-checks about marijuana at PolitiFact.com, PunditFact.com and PolitiFact.com/Florida.